The present invention relates generally to illuminated signs and light boxes. More specifically the invention relates to a backlit illuminated sign which is easily changeable and is as bright or in many instances substantially brighter than neon, even in daylight. This provides a sign that is more flexible than neon and, most important, substantially less expensive to manufacture. Over the years, neon signs have remained a popular choice for window signs, point of purchase signs, and other promotional signs due to their ability to capture customers attention. Throughout this description, the industry accepted term neon is used as a generic term which includes all cold cathode luminous tubes regardless of the specific type of inert gas used to fill the tube. One of the reasons neon signs are so effective is that the luminous tube of the neon sign is typically viewed directly by the observer rather than having a light source located behind a diffusing sign face as is the case for conventional backlit signs. Because the observer is able to look directly at the light source of the neon sign, this type of sign is able to stand out in a wide variety of ambient lighting situations including direct sunlight. Also, neon provides a three dimensional aspect to a sign which is not possible using conventional backlit signs. This three dimensional aspect adds significantly to the appeal of neon signs. However, the typical neon sign has several major drawbacks.
Traditional neon signs are made using glass tubing which is bent by a skilled neon glass bender. This results in several of the major disadvantages of neon signs. First, the bending of the luminous tube which makes up the neon sign is a relatively expensive process due to the labor involved. It has proved to be very difficult to reduce this cost by automating the tube bending process. Second, since conventional neon signs are made up of custom bent luminous tubes, they are not easily changeable in situations where it is desirable to change the design of the face of the sign from time to time. If the design of the neon sign becomes outdated or if the message on the sign needs to be changed, an entirely new and expensive custom bent tube must be produced and the sign must be reassembled by a qualified neon sign servicer in order to make any changes. And third, luminous tubes are only available in certain colors and certain tube diameters. Because of this, the design of the neon sign is limited to these certain colors and limited to designs made up of lengths of these certain diameter bent tubes. This makes it difficult to reproduce design features such as large patches of evenly lighted areas or other design features that can not be reproduced using the linear characteristics of neon tubes.
Another disadvantage of typical neon signs is that they require relatively high voltages to light the neon tube. These high voltages associated with neon signs create more difficult safety concerns compared with other types of signs used to provide small portable signs which are often to be handled by sign owners rather than a qualified sign servicer. The high voltages of neon signs require the use of more expensive components for insulating and properly isolating the high voltages from potential contact with the general public and people handling the signs. Also, the more specialized construction of the neon sign necessitated by the high voltages makes it virtually impossible for the typical sign owner to safely and properly service their own sign. For example, a sign owner may be able to safely replace a burned out fluorescent bulb in a typical backlit sign, however, the owner would not typically be able to safely replace a neon tube in a neon sign.
Another problem with neon signs is that the glass tubing making up a neon sign is extremely fragile making it difficult to manufacture the sign at a central location and ship the sign to the final destination without suffering a significant amount of shipping damage. This problem of transporting neon signs further increases the costs of the sign. To overcome this problem, neon signs are often produced locally to avoid shipping. However, this prevents manufacturers from being able to achieve significant economies of scale.
Over the years, several different approaches have been proposed to overcome the above described problems associated with typical neon signs while still retaining the same attention grabbing characteristics associated with neon signs. U.S. Pat. No. 2,080,679, issued to Ellinn D. Vissing, apparently attempts to overcome the flexibility problems associated with neon signs. Specifically, Vissing describes a neon sign using a grid of zig zagged, parallel running luminous tubes (e.g. neon) which are used in combination with reflectors to backlight a changeable sign face. The sign face is coated with an opaque coating which may then be selectively erased to form a desired design on the face of the sign. This approach addresses the problem of changeability of the sign face but still requires a luminous tube to be bent into the zig zag shape resulting in an expensive sign due to the labor involved. Also, since a luminous tube is used, the sign is limited to the color or colors of the tubes selected for backlighting. Furthermore, the problems described above associated with the high voltage, the servicing of the sign, and the fragile nature of the luminous tube all still remain using this approach.
In another approach currently being utilized which was developed subsequent to the neon tube approach just described, curvilinear grooves having a desired sign face design are etched into two sheets of glass. These sheets of glass are laminated together with the etched grooves adjacent to one another forming a tubular opening within the resulting laminated sheets of glass. The tubular opening within the sheets of glass is vacuum pumped, filled with gas, and sealed in a manner similar to conventional luminous tubes to form the face of a neon sign. This approach allows the process of forming the sheets of glass to be automated using an etching machine to etch the two sheets of glass. Although this reduces the labor involved in forming the sign, this approach remains expensive due the high equipment and tooling costs. Furthermore, this approach still has the problems of not being easily changeable, being limited to certain colors and line shapes for design features, using high voltage, and the difficulties associated with servicing the sign as described above.
Presumably in an attempt to overcome some of the drawbacks described above, still another approach has been commercialized. This approach uses a completely different arrangement in an attempt to provide a sign with the visual impact of a neon sign. In this approach, a conventional fluorescent light bulb backlit sign light box is used. This light box backlights a sign face having an array of color tinted, light channeling pegs supported within the sign face to form a desired sign face design. The light channeling pegs are inserted through openings in the sign face with the back end of each peg exposed to the interior of the light box and the front end of each peg protruding through the front of the sign face. The back end of the light channeling pegs gather light from the light box and direct the light out through the front end of the pegs in a manner similar to fiber optic cable. This tends to give the viewer the impression that each peg is a small light bulb, LED, or other such light source. This approach uses standard fluorescent backlighting and results in a bright sign which therefore eliminates the problems associated with the high voltage used with neon signs. However, the process of inserting all of the required pegs necessary to form a desired sign face design is extremely labor intensive and therefore expensive, and the sign still has the problem of not being easily changeable. Also, this approach limits the sign face design to a design that can be formed using an array of pegs or dots and does not allow for continuous or linear features in the sign face design.
Other approaches using conventional fluorescent light bulb backlit signs have been used to attempt to simulate neon signs. Conventional fluorescent bulb backlit signs typically include one or more fluorescent light bulbs supported within the light box housing. The housing may include reflectors to help spread the light over the face of the sign. The interior of the housing and the reflectors are typically painted white to reflect the light and further aid in more evenly backlighting the sign face. The approaches using conventional fluorescent light bulb backlit signs to simulate neon signs typically include various sign faces coated with various coatings which are meant to fluoresce or glow in a manner similar to a luminous tube. Heretofore, these coatings have been light diffusing coatings since, prior to the present invention, viewing fluorescent light bulbs directly was generally taboo in the sign industry. These signs eliminate the high voltage problems associated with neon signs, provide for a relatively easily changeable sign face, and dramatically reduce the cost of the sign. However, because these coatings and the typical sign face associated with a conventional fluorescent light bulb backlit sign diffuse light, these approaches do not create the brightness and therefore the visual impact associated with directly viewed neon signs.
The present invention provides an arrangement for a fluorescent light bulb backlit sign that results in an illuminated sign which is capable of generally simulating the look of a neon sign and which provides a sign that is even brighter and more visually arresting than traditional neon signs. This sign arrangement provides an easily changeable sign face and allows complete flexibility in selecting colors, shapes, and other design features of the sign face. Because standard fluorescent light bulbs are used, this arrangement provides these advantages at a cost substantially less than that of a comparable neon sign. Also, by using standard fluorescent light bulbs, the servicing and safety problems associated with the high voltage used in neon signs are eliminated. Furthermore, since the fluorescent bulbs may be easily installed and replaced by the eventual sign owner, the fluorescent tubes may be removed from their sockets for shipping and properly packaged dramatically reducing the chances of shipping damage.